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arXiv · 2610.27144

Regularization effects on the observational appearance of asymmetric thin-shell wormholes from a new string-cloud geometry

Zijun Zhong·Jonathan A. Rebouças·Edson Otoniel·Minyong Guo
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Abstract

We investigate how rational regularization of the new Letelier--Alencar string-cloud geometry changes the optical appearance of reflection-asymmetric thin-shell wormholes. We compare junctions with two nonregular exteriors, a regular observer exterior paired with a nonregular one, or two regular exteriors at fixed leading asymptotic masses, throat radius, string strength and regulator fractions. Critical scales, ray classes, orbit numbers and transfer functions are combined with three emission profiles and matched black-hole controls. Face-on and inclined images use the same prescribed emitter motion: circular timelike geodesics outside the innermost stable circular orbit and an inward plunge conserving its specific energy and angular momentum inside. Although the core is excised, regularization changes the retained exterior and throat matching. For the sampled parameters, the observer critical screen impact decreases from $10.392μ_1$ to $9.642μ_1$, where $μ_1$ is the observer-side asymptotic mass scale. Regularizing the second exterior then contracts the reflected interval from $3.890μ_1$ to $1.248μ_1$ without changing ordinary observer-side rays. Returned brightness depends on source support and velocity-dependent frequency shifts: the regular--regular image nearly coincides with its black-hole control for the outer-edge emission model face-on, while inner emission reveals returned structures. At large sampled inclination that near-degeneracy can be lifted. This separates regularization-dependent propagation from the emission and viewing conditions that determine its image contrast.

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Zijun Zhong, Jonathan A. Rebouças, Edson Otoniel, Minyong Guo. 2026-10-19. Regularization effects on the observational appearance of asymmetric thin-shell wormholes from a new string-cloud geometry. https://arxiv.org/abs/2610.27144

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